<template>
  <!-- 商品分类导航 -->
  <div class="type-nav">
    <div class="container" @mouseleave="leaveIndex" @mouseenter="enterShow">
      <h2 class="all">全部商品分类</h2>
      <transition name="sort">
        <div class="sort" v-show="show">
        <div class="all-sort-list2" @click="goSearch">
          <!-- 一级 -->
          <div class="item" v-for="(c1,index) in categoryList" :key="c1.categoryId"
            :class="{ active: currentIndex == index }">
            <h3 @mouseenter="changeIndex(index)">
              <a :data-categoryName = "c1.categoryName" :data-category1Id = "c1.categoryId">{{c1.categoryName}}</a>
            </h3>
            <!-- 二级 -->
            <div class="item-list clearfix" :style="{display:currentIndex==index?'block':'none'}">
              <div class="subitem" v-for="(c2) in c1.categoryChild" :key="c2.categoryId">
                <dl class="fore">
                  <dt>
                    <a :data-categoryName = "c2.categoryName" :data-category2Id = "c2.categoryId">{{c2.categoryName}}</a>
                  </dt>
                  <dd>
                    <!-- 三级 -->
                    <em v-for="(c3) in c2.categoryChild" :key="c3.categoryId">
                      <a :data-categoryName = "c3.categoryName" :data-category3Id = "c3.categoryId">{{c3.categoryName}}</a>
                    </em>
                  </dd> 
                </dl>
              </div>
            </div>
          </div>
        </div>
      </div>
      </transition>
      <nav class="nav">
        <a href="###">服装城</a>
        <a href="###">美妆馆</a>
        <a href="###">尚品汇超市</a>
        <a href="###">全球购</a>
        <a href="###">闪购</a>
        <a href="###">团购</a>
        <a href="###">有趣</a>
        <a href="###">秒杀</a>
      </nav> 
    </div>
  </div>
</template>

<script>
import {mapState} from 'vuex'
//引入lodash的节流
import throttle from 'lodash/throttle'
export default {
  name:'TypeNav',
  data(){
    return {
      currentIndex: -1,
      show: true
    }
  },
  methods:{
    //节流
    changeIndex:throttle(function(index){
      this.currentIndex = index
    },50),

    //鼠标移除列表消失
    leaveIndex(){
      this.currentIndex = -1
      if(this.$route.path!='/home'){
        this.show = false
      }  
    },

    //鼠标移入列表显示
    enterShow(){
      this.show = true
    },

    //路由跳转搜索
    goSearch(e){
      let {categoryname,category1id,category2id,category3id} = e.target.dataset
      if(categoryname){
        console.log(e);

        //整理路由跳转参数
        let location = {name: 'search'}
        let query = {categoryName:categoryname}

        if(category1id){
          query.category1Id = category1id
        }else if(category2id){
          query.category2Id = category2id
        }else if(category3id){
          query.category3Id = category3id
        }
        //整理参数
        location.query = query
        //路由跳转
        this.$router.push(location)
      }
    } 
  },
  mounted(){
    //通知vuex发请求,转移到app
    // this.$store.dispatch('home/categoryList')

    //如果不是/home组件，将typenav隐藏
    if(this.$route.path!='/home'){
      this.show = false
    }
  },
  computed:{
    ...mapState('home',['categoryList'])
  },
}
</script>

<style scoped lang="less">

    .type-nav {
      border-bottom: 2px solid #e1251b;
  
      .container {
        width: 1200px;
        margin: 0 auto;
        display: flex;
        position: relative;
  
        .all {
          width: 210px;
          height: 45px;
          background-color: #e1251b;
          line-height: 45px;
          text-align: center;
          color: #fff;
          font-size: 14px;
          font-weight: bold;
        }
  
        .nav {
          a {
            height: 45px;
            margin: 0 22px;
            line-height: 45px;
            font-size: 16px;
            color: #333;
          }
        }
  
        .sort {
          position: absolute;
          left: 0;
          top: 45px;
          width: 210px;
          height: 461px;
          position: absolute;
          background: #fafafa;
          z-index: 999;
  
          .all-sort-list2 {
            .item {
              h3 {
                line-height: 30px;
                font-size: 14px;
                font-weight: 400;
                overflow: hidden;
                padding: 0 20px;
                margin: 0;
  
                a {
                  color: #333;
                }
              }
  
              .item-list {
                display: none;
                position: absolute;
                width: 734px;
                min-height: 460px;
                background: #f7f7f7;
                left: 210px;
                border: 1px solid #ddd;
                top: 0;
                z-index: 9999 !important;
  
                .subitem {
                  float: left;
                  width: 650px;
                  padding: 0 4px 0 8px;
  
                  dl {
                    border-top: 1px solid #eee;
                    padding: 6px 0;
                    overflow: hidden;
                    zoom: 1;
  
                    &.fore {
                      border-top: 0;
                    }
  
                    dt {
                      float: left;
                      width: 54px;
                      line-height: 22px;
                      text-align: right;
                      padding: 3px 6px 0 0;
                      font-weight: 700;
                    }
  
                    dd {
                      float: left;
                      width: 415px;
                      padding: 3px 0 0;
                      overflow: hidden;
  
                      em {
                        float: left;
                        height: 14px;
                        line-height: 14px;
                        padding: 0 8px;
                        margin-top: 5px;
                        border-left: 1px solid #ccc;
                      }
                    }
                  }
                }
              }
  
              // &:hover {
              //   .item-list {
              //     display: block;
              //   }
              // }
            }
            .active {
              background-color: skyblue;
            }
          }
        }

        //过度动画开始
        .sort-enter{
          height: 0px;
        }
        //过度动画结束
        .sort-enter-to{
          height: 461px;
        }
        //定义动画时间速率
        .sort-enter-active{
          transition: all 0.5s linear;
        }
      }
    }
</style>